From 059f3ff19afa3aa3112492e234382f097c27b0fa Mon Sep 17 00:00:00 2001 From: Lior David Date: Tue, 21 Apr 2020 13:40:13 +0100 Subject: wil6210: fix length check in __wmi_send [ Upstream commit 26a6d5274865532502c682ff378ac8ebe2886238 ] The current length check: sizeof(cmd) + len > r->entry_size will allow very large values of len (> U16_MAX - sizeof(cmd)) and can cause a buffer overflow. Fix the check to cover this case. In addition, ensure the mailbox entry_size is not too small, since this can also bypass the above check. Signed-off-by: Lior David Signed-off-by: Maya Erez Signed-off-by: Kalle Valo Signed-off-by: Lee Jones Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/ath/wil6210/interrupt.c | 22 +++++++++++++++++++++- drivers/net/wireless/ath/wil6210/wmi.c | 2 +- 2 files changed, 22 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/wil6210/interrupt.c b/drivers/net/wireless/ath/wil6210/interrupt.c index 64046e0bd0a2..a37533cffc7c 100644 --- a/drivers/net/wireless/ath/wil6210/interrupt.c +++ b/drivers/net/wireless/ath/wil6210/interrupt.c @@ -356,6 +356,25 @@ static void wil_cache_mbox_regs(struct wil6210_priv *wil) wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx); } +static bool wil_validate_mbox_regs(struct wil6210_priv *wil) +{ + size_t min_size = sizeof(struct wil6210_mbox_hdr) + + sizeof(struct wmi_cmd_hdr); + + if (wil->mbox_ctl.rx.entry_size < min_size) { + wil_err(wil, "rx mbox entry too small (%d)\n", + wil->mbox_ctl.rx.entry_size); + return false; + } + if (wil->mbox_ctl.tx.entry_size < min_size) { + wil_err(wil, "tx mbox entry too small (%d)\n", + wil->mbox_ctl.tx.entry_size); + return false; + } + + return true; +} + static irqreturn_t wil6210_irq_misc(int irq, void *cookie) { struct wil6210_priv *wil = cookie; @@ -391,7 +410,8 @@ static irqreturn_t wil6210_irq_misc(int irq, void *cookie) if (isr & ISR_MISC_FW_READY) { wil_dbg_irq(wil, "IRQ: FW ready\n"); wil_cache_mbox_regs(wil); - set_bit(wil_status_mbox_ready, wil->status); + if (wil_validate_mbox_regs(wil)) + set_bit(wil_status_mbox_ready, wil->status); /** * Actual FW ready indicated by the * WMI_FW_READY_EVENTID diff --git a/drivers/net/wireless/ath/wil6210/wmi.c b/drivers/net/wireless/ath/wil6210/wmi.c index 61419d1b4543..3f6ac1ca0e57 100644 --- a/drivers/net/wireless/ath/wil6210/wmi.c +++ b/drivers/net/wireless/ath/wil6210/wmi.c @@ -209,7 +209,7 @@ static int __wmi_send(struct wil6210_priv *wil, u16 cmdid, void *buf, u16 len) uint retry; int rc = 0; - if (sizeof(cmd) + len > r->entry_size) { + if (len > r->entry_size - sizeof(cmd)) { wil_err(wil, "WMI size too large: %d bytes, max is %d\n", (int)(sizeof(cmd) + len), r->entry_size); return -ERANGE; -- cgit v1.2.3